1. Field of the Invention
The invention relates to a device for sealing the end of a heat-shrunk sleeve enclosing a branch connection of electrical or optical cables. The device grips the outside of the sleeve between the cable branches and keeps opposing parts of the sleeve between the cables in contact with each other while they cool following heat shrinking of the sleeve.
2. Description of the Prior Art
A pamphlet from the Raychem Company entitled "Thermofit Tubing Splice Encapsulation Directions" introduces a technique whereby the ends of two cables are inserted into a shrinkable sleeve. The inside of the shrinkable sleeve is coated with hot-melt adhesive. While the sleeve is hot, the area of the bushing between the cables is clamped together with a pliers-type tool. The hot-melt adhesive liquefies during the shrinking, and is forced into the empty spaces by the shrinking sleeve. The tool can be removed after the branch connection has cooled. After cooling, the hot-melt adhesive keeps the opposing areas between the cables together and seals the inlet area. The shape of the pliers-type tool is disclosed as needle-nosed.
U.S. Pat. No. 4,298,415 describes a clamp, instead of the pliers-type tool, which is pushed from the end of the bushing toward the inlet area of the bushing between the cables. In a preferred configuration, a three-legged metal clamp is used, one leg of which is located inside the sleeve, while the other two are outside. The leg on the inside of the sleeve is coated with hot-melt adhesive. During heat shrinking, heat is transmitted by the metal clamp to the inside of the sleeve, where it liquefies the hot-melt adhesive. The technique was used successfully to produce sleeves for communication cables. The use of this well known clamp is particularly difficult when the end of the sleeve is not easily accessible. In addition, the installer needs both hands, since installation of the clamp requires the inlet area to be squeezed together. Certain precautions must be taken to prevent the clamp from coming off the sleeve during heat shrinking, and increases the clamp's manufacturing costs. Thus, it is known to provide the clamp with a saw tooth profile, or to manufacture the clamp from a heat restoring alloy.
DE-GM 9,100,359 describes a tool with which the end of the sleeve located between the cable branches can be squeezed together before, during or after heat shrinking. This pliers-type tool is made of metal wire. Clamping pressure is provided by a spring. In the same manner as described earlier, the tool according to DE-GM 9,100,359 is also inserted at the end of the sleeve, i.e. sufficient space must be provided between the cable branches to manipulate the clamp or the tool.